MrBucket

Hello, everyone. I'm building an 8x8x8 cube and have eight TLC5951s and a handful of a P-channel Power MOSFET found at http://www.ti.com/product/csd25401q3. I'm pretty new to embedded electronics, and - specifically - transistors, so I was wondering how I could use the driver and transistor in combination to be able to mux one horizontal plane at a time. All of the RGB LEDs in one horizontal plane share an anode. My µC runs off of 3.3V and defaults to an internal pull-up. Thanks!

Each TLC device will control a row of LEDs. Eight devices will control 8 rows, that's 1 layer. All the anodes from 1 layer will have current sourced from 1 PNP, or P-channel, device.All the LEDs in a column get their cathodes connected in parallel, to a single TLC pin.Send out TLC data for 1 layer, enable that layer's current source.Repeat the next layer.

MrBucket

Each TLC device will control a row of LEDs. Eight devices will control 8 rows, that's 1 layer. All the anodes from 1 layer will have current sourced from 1 PNP, or P-channel, device.All the LEDs in a column get their cathodes connected in parallel, to a single TLC pin.Send out TLC data for 1 layer, enable that layer's current source.Repeat the next layer.

Thanks. Having the drain connected to 3.3V, source to the TLC5951 pin, and switching the gate between GND and 3.3V has no effect (LED is always on).